Several lines of evidence suggest greater aerobic and cardiovascular adaptations after high-intensity exercise than with moderate levels in patients with coronary artery disease or left ventricular dysfunction function and in healthy subjects. Aerobic interval training (AIT) involving periods at 90% of VO2peak has been shown to rescue impaired cardiomyocyte contractility, attenuate myocardial hypertrophy, and reduce myocardial expression of atrial natriuretic peptide in animal model of post-infarction heart failure. However, underlying mechanisms of AIT-improved regulations remain unclear.